Field of the Invention
The present invention relates to a method for manufacturing a liquid ejection head.
Description of the Related Art
Like ink jet print heads, some liquid ejection heads which eject liquid as droplets from a plurality of elements are configured to have a substrate having elements for generating ejection energy arranged thereon, and a resin layer laminated on the substrate, the resin layer having formed thereon a flow path for guiding the liquid to each of the elements.
Japanese Patent Publication No. H06-45242 (1994) explains a process of manufacturing such a liquid ejection head by a casting method. More specifically, first, on a substrate having energy generating elements arranged thereon, a mold of an ink flow path is patterned by using a photosensitive material. Then, the formed mold pattern is coated with a resin and the resultant is set. Furthermore, after forming an ejection port which is in communication with the mold of the flow path on the coated member, the photosensitive material used for the mold pattern is removed. Accordingly, an area resulting from the removal of the photosensitive material forms a flow path, and a liquid ejection head having arranged therein an energy generating element, a liquid path for guiding liquid to the energy generating element, and an ejection port for ejecting the liquid is completed.
Meanwhile, U.S. Pat. No. 6,716,767 discloses a method for preventing concavo-convex portions from being generated also on a resin surface in accordance with a plurality of concavo-convex portions formed on a surface of a substrate when a casting method is used to coat the substrate with a resin having a high viscosity. More specifically, there is explained a process including providing various kinds of materials for adjusting steps on the substrate, applying the resin having a high viscosity to the surface of the substrate, further, bringing a mold having a smooth surface into contact with an upper surface of a resin layer, and then allowing the resin layer to be set.